It becomes popular that a video image display apparatus such as a television is mounted on a vehicle, such as a car, airplane, train, or ship. In recent years, mounting a display for a person on a backseat has been increased. Such a display includes a display hung down from a ceiling, but this type has a problem of blocking the rearward visibility of a driver. Therefore, a display is sometimes mounted on a head restraint of a front seat.
Patent Literature 1 discloses a configuration in which a video image display apparatus such as a television is mounted on a heat restraint of a front seat. This video image display apparatus is configured to be capable of adjusting an angle of a screen with respect to a vertical direction. The angle of the screen is adjusted by pushing a lower part of the screen, or by inserting a finger below the display and pulling the lower part of the display. When the lower part of the display is pulled to adjust the angle, the upper part of the screen is defined as a supporting point so as to adjust the angle of the screen. However, in order to make the adjustment described above, a user has to insert his/her finger at the lower part of the display to pull the lower part of the display. For this operation, a recessed portion into which a finger is inserted has to be formed at the lower part of the display, which entails a problem of deteriorating a design of the display.
In order to solve this problem, it has been considered that a screen-angle adjusting mechanism disclosed in Patent Literature 2 is employed, for example. In this screen-angle adjusting mechanism, an angle of a screen is adjusted by using a ratchet wheel mounted on a rotation axis and a lock release member of the ratchet wheel. The angle of the screen is adjusted in a stepwise manner by the ratchet wheel in a push-in direction of the screen. When the screen is fully pushed, the lock of the ratchet wheel is released by the lock release member. The screen is returned to the angle of an initial position by elastic force of a spring.
However, in the screen-angle adjusting mechanism disclosed in Patent Literature 2, the angle of the screen can be adjusted only by an amount corresponding to a space between the ratchets of the ratchet wheel, which entails a problem that a delicate angular adjustment cannot be attained.
When the screen with the adjusting mechanism is mounted on a head restraint of a front seat, a head of a person sitting in the front seat and the position of the screen might be close to each other. In the above-mentioned screen-angle adjusting mechanism, the lock member is brought into contact with the ratchet wheel upon adjusting the angle of the screen, whereby a collision sound is produced. Accordingly, every time a person on a backseat adjusts the angle of the screen, an operation sound upon adjusting the angle of the screen is produced, which might give uncomfortable feeling, i.e., give harsh sound, to the person sitting in the front seat.